Improvement in lathes for cutting screws



J. TANGYE. Screw Threading Machine. 1

No. 56,339. Patented July 10, 1866. i

J)! r 1 Jf I I I591.

JV 5 6 v C I; I v 3 s .17 T 05 J1 Q U W m p 1 fles'sea IT'I-UnfO-rn' M WUNITED STATES PATENT OFFICE.

JOSEPH TANGYE, OF BIRMINGHAM, ENGLAND.

lMPROVEMENT IN LATHES FOR CUTTING SCREWS.

To all whom it may concern.-

Be it known that I, .Tosnrn TANGYE, of Birmingham, England, haveinvented an Improvement in Lathes for Cutting Screws, of which thefollowing is a specification.

This invention relates to a peculiar arrangement and combination ofmachinery or apparatus for cutting screws, whereby a considerable savingin time is effected, inasmuch as I am enabled to out two, three, or morescrews simultaneously.

In carrying out my said invention in practice I construct a lathe-bedsimilar to an ordinary screw-cutting lathe-bed, but of a sufficientwidth to accommodate two or more screwblanks side by side, upon whichscrew-threads are to be out in lieu of being only wide enough to receivea single screw-blank, as heretofore. The several screw-blanks arecarried between two sets of corresponding centers, one set be- 1 ingarranged and constructed in the ordinary manner and made adjustable inorder to admit of the blanks being inserted and removed, while the otherset is fitted in a headstock secured to the driving end of thelathe-bed. This headstock extends the full width of the bed, and carrieson its outer face a fixed axis or' stud center, upon which revolvesfreely a cone of driving-pulleys, to which is secured so as to rotatewith them a spur-pinion in gear with a spur-wheel on a short shaftworking in a bushed bearing in the headstock. On the inner end of thisshort shaft there is keyed a spur-pinion, which is in gear with anddrives simultaneously two spur-pinions, respectively, carried by two ofthe fixed centers in the head stock, and round which they rotate freely.The third center, (when three are used,) or that next to the front ofthe lathe, carries a spurpinion corresponding to the pinions on theother two centers, and deriving its motion from the other two byacarrier-pinion workin gloose on a stud-center in the head-stock.

Itwill thus be seen that on rotating the drivin g-pulleys the whole ofthe pinions on the centers in the head-stock will be rotatedsimultaneously and in the same direction.

The rotatorymotion of the pinions above referred to is imparted to thethree screw-blanks to be cut into screws by means of a projecting pinfrom the face of each pinion coming in contact with a radial pin securedto the head of each of the blanks, and hence as the pinions revolve theywill carry round with them their respective screw-blanks.

The slide-rest which carries the cuttin g-tools is provided with as manyholders as there are tools required, each holder being provided with itsown tool adjusting or setting screw.

The traverse motion is imparted to the sliderest in the usual mannerfrom a leading-screw working in a split nut on the slide-rest and drivenby any convenient or well-known arrangement or combination ofchange-wheels, according to the pitch of the screw-thread to beproduced.

The depth of cut of the several tools is regulated by a singlefeeding-screw carried by the slide-rest, as in single screw-cuttinglathes, with this difference, that it operates upon two, three, or moretool-holders simultaneously.

The rest of the parts are similar to those hitherto employed in machinesof this class and need no further description.

' Having set forth the nature of my inven tion, 1 shall now proceed moreparticularly to describe the same, and for that purpose I shall refer tothe explanatory figures on the sheet of drawings hereunto annexed, thesame letters of reference indicating corresponding parts in all thefigures.

Figure 1 represents a side elevation of a multiple screw-cutting latheconstructed and arranged so as to cut three screws simultaneously inaccordance with my invention. Fig. 2 is a corresponding plan of thesame; and Fig. 3 is an inside viewof the head-stock, showing thearrangement of the gearing which rotates to the screw-blanks.

A is the lathe-bed supported on the standards B B, and carrying thefixed head-stock O and adjustable poppet-head D. E E E are three centersfitted into the head-stock O, and E E E are corresponding adjustablecenters carried by the movable poppethead D. Between these two sets ofcenters E E are supported the three screw-blanks F F F to which arotatory motion is imparted from the driving-pulleys G by means of thefollowing arrangement of gearing: The driving-pulleys revolve loosely onthe stud-center H, fixed in the upper part of the head-stock, and withthem rotates the spur-pinion I, which maybe made in one piece with orsecured to the driving-pulleys. This pinion gears into the wheel K faston the outer end of a short shaft, L, which works in a bushed bearing,M, on the head-stock. On the inner end of the short shaft L there iskeyed the pinion N, Fig. 3, which gears into the spur wheels or pinionsO 0 revolving loosely upon the corresponding centers E E The wheel orpinion O on the center L derives its motion from the Wheel or pinion Oby the intervention of the carrier-pinion N working loose on astud-center, I, in the inner face of the head-stock (3. Into the face ofeach of the wheels 0 O 0 there is fitted a projecting stud or pin, a, aa ,'which pins, on being carried round, come in contact with radial armsor studs 1) 1) b fixed into the ends of the respective screw-blanks F FF and impart a rotatory motion thereto in a uniform direction.

Q, is the slide-rest, which extends across the lathe-bed and carries asmany tools or cutters c c c as there are screws to be cut at one time.The several cutters are all separately adjusted in their respectiveholders R B B, and these holders are fed up to or removed from the workby means of the ordinary feeding-screw S, which works the three holderssimultaneously.

T is the usual leading-screw, which works through a split nut on theunder side of the slide-rest and derives its motion from the spurwhcel 0through the intervention of the pinion U and train of change-wheels V V,which is well understood by mechanics. On the slide-rest arriving at theend of its traverse it is run back by means of the rack W and pinions Y,worked by a winch-handle or otherwise.

It will be obvious that by increasing the number of centers and addinggearing to cor-.

respond any additional number of screws may be simultaneously cut,provided the bed be made wide enough to accommodate a sliderest of alength sufficient to carry the number of tools required.

Having now described and particularly ascertained the nature of myinvention and the manner in which the same is or may be used or carriedinto effect, I would observe, in conclusion, that I do not claim thecombination of a slide-rest with a tool or cutter; but

What I do claim is- 1. The combination, in ascrew-cutting lathe, of asingle slide-rest with two or more tools or cutters which operatesimultaneously upon two or more different screw-blanks, all constructedand arranged substantially as herein described.

2. The combination, in a screw-cuttinglathe, of a head-stock andpoppet-head, each provided with two or more centers, when constructedand arranged substantially as herein described.

3. In a screw-cutting lathe constructed and arranged as hereindescribed, the special gearing actuated by the driving-pulleys for thepurpose of rotating two or more screw-blanks simultaneously in the samedirection, as hereinbefore described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

JOSEPH TANGYE.

Witnesses G. E. MATHEWS,

Solicitor and Notary, Birminghmn. ORow'rHER DAVIS,

His Clerk.

